`np.float64(np.nan) % 1` gives warning

The following operations correctly return nan without warning:

import numpy as np

np.nan + 1
np.nan - 1
np.nan * 1
np.nan / 1
np.nan % 1

So do

np.float64(np.nan) + 1
np.float64(np.nan) - 1
np.float64(np.nan) * 1
np.float64(np.nan) / 1

Taking %, however, does give a warning:

np.float64(np.nan) % 1

<ipython-input-49-4b0062698971>:1: RuntimeWarning: invalid value encountered in double_scalars
  np.float64(np.nan) % 1

This inconsistency extends to all numpy float types.

[arubiales]

@seberg Yes of course. It’s my first contribution to Numpy and after all the hours I want to finish the job properly. I didn’t enter in the .src files because I thought it was for Windows SO only…

I have done similar changes to the file to avoid the warning and I get to avoid with NaN as a second input. Right now I will do:

• Think the perfect way to do it (now it is a draft)
• Do the same with np.inf to avoid also the error with this constant.

Thank you very much for your help.

[seberg]

@arubiales if the warning is actually manually set, it would be something like npy_set_floatstatus. But most likely the opposite is the case: The C code (machine code), sets an error flag (the CPU does this, or well, the basic math library) for a certain operation. And our code would have to avoid taking that code path alltogether.